If I understood correctly you want to place a object to position? Don't think this has anything to do with physics but here is one way to do it:
Code:
VECTOR ball_pos;
function ball_func(){
vec_set(ball_pos,vector(x1,y1,z1);//x1-z1 are the numbers of pos
my.x = ball_pos.x;
my.y = ball_pos.y;
my.z = ball_pos.z;
...
}